A flexible hybrid power system.

That’s the thinking behind Perkins’ Project Coeus, an exciting, wide-ranging Perkins initiative that’s been developed to help customers in the off-highway industry as they navigate the evolving energy landscape.

The journey to a more sustainable future will also create a more resilient energy system, reducing our reliance on fuels such as diesel and ‘spreading the load’ across a range of alternative fuel sources, all with improved sustainability credentials.

Thus Project Coeus. Named after the Greek god of resolve and intelligence and partially supported by a £11.14m UK government grant through the Advanced Propulsion Centre, Coeus sees Perkins partner with UK engineering expertise: Loughborough University’s Wolfson School of Mechanical, Electrical and Manufacturing Engineering, and e-powertrain specialists Equipmake.

Launched in October 2023, the three-and-a-half-year project is built around a commitment to develop an innovative ‘drop-in’ hybrid power unit, suitable as a direct replacement for the diesel equivalent.

Powernews caught up with Paul Moore, Perkins integrated powertrain engineering manager and Project Coeus lead at a recent press briefing in London, UK, to find out more.
 

Complete power solution

“This is more than just proving a concept,” Paul contends. “Perkins has always been renowned for its engines, yes, but hand-in-hand with that is the way we work with OEMs to provide a complete power solution.

“That’s especially the case for smaller OEMs, who can and do tap into Perkins’ engineering expertise in pursuit of the optimum solution.”

Paul explains that the majority of Perkins’ engine production volume supports a relatively narrow range of machine types. The smaller OEMs, conversely, have close to 100 different applications. “It’s difficult for them. They can struggle to adopt new technology. There are too many barriers for them to overcome.

“What Coeus seeks to do is to make it easier to adopt these new energy technologies,” he explains.

“First, we deliver ‘drop-in’ diesel performance. Then we minimise OEMs’ power system design integration demands, as well as application validation and installation (A&I) demands.”

Together, Paul says, this should help OEMs become more confident about the adoption of lower-carbon intensity power systems and thus help to speed up the transition.

It’s this thinking, too, that’s behind the decision to go not with a single alternative fuel, but with several. “We’ve got used to diesel being the dominant fuel source and, while it would be good to pivot to a single replacement fuel, in reality that’s just not going to happen.

“There’s too much global diversity in fuel supply. And by pursuing different fuels, we can create a more resilient global fuel system, one that leverages the availability and affordability of different fuels in different regions and allows customers to use different fuel types with minimal disruption to their products.”

The four fuels selected for inclusion in Project Coeus – ethanol, methanol, bio-methane and hydrogen – have one characteristic in common: they are all spark-ignited fuels. That’s important, says Paul, in creating the common combustion platform on which Coeus relies.

“We need an engine that can perform consistently, regardless of the fuel by which it’s powered,” he explains. “Whether it’s a machine in Brazil, drawing on the already well-established ethanol production infrastructure, or the same machine in Europe that’s going to be fuelled by the nascent green hydrogen industry, we want to be able to assure the customer that despite different properties, the performance characteristics will be the same.”

To build this advanced integrated power unit, Project Coeus brings together three key components: a spark-ignited lower-carbon intensity internal combustion platform, supported by an advanced hybrid system, both of which are managed by a highly capable digitised control system.

“Integrating these three components creates the advanced ‘drop-in’ power unit that, as far as the customer is concerned, is almost indistinguishable in interface and performance from the diesel-powered unit it seeks to supplant,” enthuses Paul. “With our advanced control systems expertise, we can build a self-optimising power unit that has the system intelligence to adapt itself, automatically, to each fuel.

“This minimises the integration engineering required. This unit’s power density, response, and so on, will be indistinguishable from a diesel-powered solution.”
 

Progress so far

The project’s being led from Perkins’ global engineering headquarters at Peterborough, in the UK. It’s just one of the 264 projects supported by the Advanced Propulsion Centre, an organisation founded in 2013 to help deliver the UK government’s aspiration for net-zero transportation solutions, whether in the wider automative sector or the niche vehicle and heavy-duty sectors.

During the project’s first year, Paul says they’ve made great strides. “We’ve gone from what was a paper-based project to a real, live, functioning prototype,” he buzzes. “It’s a very exciting position to find ourselves in.”

Paul’s team chose the 1206 as the core platform on which to develop the spark ignited hybrid power unit. A long-established and well-proven engine series, the six-cylinder 1206 spark ignited engine is expected to deliver 180 kW output running on hydrogen, with up to an additional 120 kW available from the advanced hybrid system – a level the team hopes to match as engine testing gets underway during the first half of 2025.

This first prototype has been designed to run on hydrogen, making it a significant milestone in Perkins’ long history by becoming the company’s first-ever hydrogen-fuelled engine.

“We’ll then be working with Loughborough University and their world-class engine optical diagnostic capabilities, giving us an unrivalled flow of information about in-cylinder flow, gas-injection dynamics and aftertreatment,” said Paul, adding: “Together, that gives us all the information we need to embark on a fully fuel-flexible engine design.”

Then it’s time to engage Equipmake and their extensive understanding of integrating hybrid components. Established in 1997, the company’s been responsible for developing electric powertrain solutions for almost every electric future – aerospace, automotive, marine, construction, buses – with an engineering heritage derived from motorsports including Le Mans and F1.

During 2026, the plan is to match the advanced prototype with the hybrid motor generator unit, to create a full power unit that can go into real-world testing.

“We’ve yet to determine the customer application in which we’ll do that testing,” Paul says, “but it’s going to be very exciting to get it underway.

“Coeus is all about delivering a robust, trusted plug-and-play power solution that is configurable, and thus capable of providing the off-highway industry with multiple solutions, all wrapped up as one.

“With this, we’ll be continuing our tradition of pushing the boundaries of off-highway power systems, ensuring our customers can make the right choices in navigating the evolving energy landscape, with robust, future-focused solutions.”